Screw structure and template system

Abstract

The invention relates to the technical field of building tools, and discloses a screw rod structure and a formwork system.The screw rod structure comprises a rod body, a screw rod and a screw rod, the sleeve is arranged on the rod body in a sleeving manner; according to the screw rod structure, the sleeve sleeves the rod body, the multiple supporting assemblies are arranged, after the screw rod structure is placed to a designated position, the rod body rotates in the forward direction relative to the sleeve, the supporting assemblies rotate in the forward direction relative to the sleeve, and therefore the screw rod structure can rotate in the forward direction relative to the sleeve; the multiple supporting assemblies form a closed contact face on the outer side of the sleeve, at the moment, concrete can be poured by fixedly matching the screw rod structure with a formwork, after the poured concrete is hardened, the rod body rotates in the opposite direction relative to the sleeve, at the moment, gaps are generated between the supporting assemblies and the concrete, and the screw rod structure can be completely drawn out of the concrete. The problems that an existing opposite-pull screw structure is large in number of using procedures, and material waste can be caused are effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of building tools, in particular to a screw rod structure and a template system. Background Art

[0002] In the current cast-in-place concrete structure, the construction process often requires a large amount of formwork. The formwork is fixed at the location where concrete needs to be cast, and the formwork is closed to form a cavity to hold the concrete, and then the concrete is cast. Since the firmness of the formwork fixation will directly affect the casting quality of the concrete, the formwork on both sides is usually fixed with a more reliable tie screw. The screw is directly inserted into the cavity of the cast concrete, and the two ends of the screw are respectively tied and fixed to the formwork on both sides by nuts. After the concrete is poured and solidified, the screw will remain in the wall and cannot be removed. Therefore, a large number of screws will be consumed while the formwork is in use. In order to reduce the use of screws, it is very important whether the tie screws can be reused.

[0003] At present, the existing screw rod mainly realizes recycling by presetting a sleeve on the outside. The sleeve is sleeved on the outside of the screw rod and is located in the cavity containing concrete together with the screw rod. The sleeve can effectively prevent the concrete from contacting the screw rod. After the concrete solidifies, the sleeve will remain in the concrete and cannot be taken out. The screw rod can be pulled out and used again. Although the screw rod of this structure can be reused, the sleeve will still be consumed. At the same time, there are many steps in the use process. The sleeve still needs to be sleeved before the screw rod is used next time. Therefore, the above structure still has the problem of many use processes and material waste. Summary of the invention

[0004] In view of this, the present invention provides a screw rod structure and a template system to solve the problem that the existing tension screw rod structure has many use processes and causes material waste.

[0005] In the first aspect, the present invention provides a screw structure, comprising: a rod body, on the outer wall of which a plurality of matching grooves are provided along the circumferential direction, the depth of at least one section of the matching grooves gradually decreases along the circumferential direction; a sleeve, which is sleeved on the rod body, and the sleeve and the rod body can rotate relative to each other; a plurality of support assemblies, which are arranged corresponding to the plurality of matching grooves, each support assembly has a matching end and a supporting surface, the matching end passes through the sleeve and matches with the corresponding matching groove, each support assembly has an extended state extending outward and a retracted state retracting inward, and the plurality of support assemblies are suitable for extending outward so that the plurality of supporting surfaces are combined to form a contact surface in contact with concrete; wherein, when the rod body rotates forwardly relative to the sleeve, the matching end moves toward the shallower side of the matching groove, and the supporting surface moves away from the sleeve, and the support assembly is in an extended state; when the rod body rotates reversely relative to the sleeve, the matching end moves toward the deeper side of the matching groove, and the supporting surface moves close to the sleeve, and the support assembly is in a retracted state.

[0006] Beneficial effect: a sleeve is sleeved on the rod body and multiple support assemblies are set. The support assemblies cooperate with the matching grooves on the rod body to achieve extension and retraction. After the screw structure is placed in the specified position, the rod body is rotated relative to the sleeve in the positive direction, and the multiple support assemblies extend outward and cooperate with each other to form a closed contact surface on the outside of the sleeve. At this time, the screw structure is fixed to the template and concrete can be poured. After the poured concrete hardens, the rod body is rotated relative to the sleeve in the opposite direction, and the multiple support assemblies retract inward. At this time, a gap is generated between the support assemblies and the concrete, and the screw structure can be completely pulled out of the concrete, eliminating the sleeve step. Only two rotations are required to separate the screw structure from the concrete, which effectively solves the problem that the existing tension screw structure has many working procedures and causes material waste.

[0007] In an optional embodiment, when a plurality of support surfaces are combined to form a contact surface, two adjacent support surfaces are overlapped.

[0008] Beneficial effects: The matching method is simple and effective. While improving the strength of the matching position of two adjacent supporting surfaces, it can also prevent concrete from passing through the joints.

[0009] In an optional embodiment, in the two overlapping support surfaces, the mating groove corresponding to the outer support surface forms an outer mating groove, and the mating groove corresponding to the inner support surface forms an inner mating groove, and the depth change rate of the outer mating groove is smaller than the depth change rate of the inner mating groove, so that the retraction speed of the outer support surface is smaller than the retraction speed of the inner support surface.

[0010] Beneficial effect: Since two adjacent support surfaces are overlapped, this arrangement can effectively avoid interference between the inner support surface and the outer support surface during the retraction process, and the structure is simple and the design is ingenious.

[0011] In an optional embodiment, each support assembly includes a support rod and a support blade, a through hole is provided on the sleeve for the support rod to pass through, one end of the support rod forms a mating end and the other end is fixedly connected to the support blade, and the side of the support blade away from the sleeve forms a support surface.

[0012] Beneficial effects: The through hole can limit the movement of the support rod, thereby effectively fixing the position of the support assembly, with a simple structure and convenient operation.

[0013] In an optional embodiment, the thickness of the supporting blade first increases gradually and then decreases gradually along the circumferential direction.

[0014] Beneficial effect: The end of each supporting blade close to the adjacent supporting blade is thinner, which is convenient for overlapping and fitting, and the middle part of the supporting blade is thicker, which improves the overall structural strength.

[0015] In an optional embodiment, a limit block is provided at the mating end of the support rod, the limit block is slidably matched with the mating groove, and the limit block is suitable for limiting the support rod from escaping from the through hole.

[0016] Beneficial effect: the limit block cannot pass through the through hole, so that the matching end of the support rod cannot escape from the through hole, and the maximum extension length of the support rod can be limited by the thickness of the limit block, and the structure is simple and reliable.

[0017] In an optional embodiment, an elastic member is further provided between the limiting block and the inner wall of the sleeve, and the elastic member is suitable for making the limiting block slide along the bottom surface of the matching groove toward the deeper side of the matching groove.

[0018] Beneficial effect: when the support rod is in the extended state, the elastic member is in the compressed state. Due to the presence of the elastic member, the limit block can fit the bottom of the matching groove as closely as possible.

[0019] In an optional embodiment, there are multiple support rods in each support assembly, and one support blade cooperates with the corresponding matching groove through multiple support rods, and the multiple support rods are arranged at intervals along the axial direction of the sleeve.

[0020] Beneficial effect: Multiple support rods can improve the support strength and prevent a single support rod from breaking when supporting.

[0021] In an optional embodiment, the end of the rod body is provided with a thread.

[0022] Beneficial effect: easy to cooperate with fixing bolts.

[0023] In the second aspect, the present invention also provides a formwork system, which includes: an inner formwork and an outer formwork, which are arranged relatively to each other; the above-mentioned screw structure, which is suitable for being passed through the inner formwork and the outer formwork; and a plurality of locking members, which cooperate with the corresponding screw structures to tie and fix the inner formwork and the outer formwork.

[0024] Beneficial effect: By using the above-mentioned screw structure in conjunction with multiple locking parts, the inner formwork and the outer formwork are tied and fixed, so that the components in the formwork system can be reused, which greatly reduces the loss of the formwork system during use and saves costs. At the same time, the screw structure is easy and quick to use and can also improve the pouring construction rhythm. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A schematic diagram of a support assembly of a screw structure in an embodiment of the present invention in an extended state;

[0027] Figure 2 for Figure 1 A schematic diagram of the support assembly of the screw structure shown in a retracted state;

[0028] Figure 3 for Figure 1 An enlarged schematic diagram of the screw structure at point A shown;

[0029] Figure 4 for Figure 1 A side view of the screw structure shown;

[0030] Figure 5 for Figure 1 A front view of a rod body of the screw structure shown;

[0031] Figure 6 for Figure 1 A front view of the support assembly of the screw structure shown;

[0032] Figure 7 for Figure 1 Side view of the sleeve of the screw structure shown.

[0033] Description of reference numerals:

[0034] 1. Rod body; 101. Matching groove; 102. Bottom surface; 2. Sleeve; 201. Through hole; 3. Support assembly; 301. Support rod; 302. Support blade; 303. Limit block. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0036] Combine the following Figures 1 to 7 , describing an embodiment of the present invention.

[0037] According to an embodiment of the present invention, on the one hand, a screw structure is provided, comprising: a rod body 1, a sleeve 2 and a plurality of support components 3, wherein a plurality of matching grooves 101 are provided on the outer wall of the rod body 1 along the circumferential direction, and the depth of at least one section of the matching groove 101 gradually decreases along the circumferential direction; the sleeve 2 is sleeved on the rod body 1, and the sleeve 2 and the rod body 1 can rotate relative to each other; the plurality of support components 3 are arranged corresponding to the plurality of matching grooves 101, each support component 3 has a matching end and a supporting surface, the matching end passes through the sleeve 2 and matches with the corresponding matching groove 101, and each support component 3 It has an extended state extending outward and a retracted state retracting inward, and the multiple support components 3 are suitable for extending outward so that the multiple support surfaces are combined to form a contact surface with the concrete; wherein, when the rod body 1 rotates forward relative to the sleeve 2, the mating end moves toward the shallower side of the mating groove 101, and the support surface moves away from the sleeve 2, and the support component 3 is in the extended state; when the rod body 1 rotates reversely relative to the sleeve 2, the mating end moves toward the deeper side of the mating groove 101, and the support surface moves close to the sleeve 2, and the support component 3 is in the retracted state.

[0038] The screw structure of this embodiment is applied, a sleeve 2 is sleeved on the rod body 1 and multiple support assemblies 3 are set. The support assembly 3 cooperates with the matching groove 101 on the rod body 1 to achieve extension and retraction. After the screw structure is placed at the specified position, the rod body 1 is rotated relative to the sleeve 2 in the positive direction, and the multiple support assemblies 3 extend outward and cooperate with each other to form a closed contact surface on the outside of the sleeve 2. At this time, the screw structure is fixed to the template and concrete can be poured. After the poured concrete hardens, the rod body 1 is rotated relative to the sleeve 2 in the opposite direction, and the multiple support assemblies 3 retract inward. At this time, a gap is generated between the support assembly 3 and the concrete, and the screw structure can be completely pulled out of the concrete, eliminating the sleeve step. Only two rotations are required to separate the screw structure from the concrete, which effectively solves the problem that the existing tension screw structure has many working procedures and causes material waste.

[0039] Herein, inward refers to a direction approaching the rod body 1 , and outward refers to a direction away from the rod body 1 .

[0040] In this embodiment, when multiple support surfaces are enclosed to form a contact surface, two adjacent support surfaces overlap and cooperate, and multiple support surfaces form a closed contact surface through overlapping cooperation. The cooperation method is simple and effective, and while improving the strength of the cooperation position of the two adjacent support surfaces, it can also prevent concrete from passing through the joint. It can be understood that as an alternative implementation, two adjacent support surfaces can also be abutted, so that the cooperation position of the two support surfaces can be smoothly transitioned, preventing concrete from entering the gap of the overlapping cooperation, and preventing the support surface from being unable to retract after the concrete solidifies.

[0041] In this embodiment, of the two overlapping support surfaces, the mating groove 101 corresponding to the outer support surface forms an outer mating groove, and the mating groove 101 corresponding to the inner support surface forms an inner mating groove. The depth change rate of the outer mating groove is smaller than the depth change rate of the inner mating groove, so that the retraction speed of the outer support surface is smaller than the retraction speed of the inner support surface. Since the two adjacent support surfaces are overlapping, this setting method can effectively avoid interference between the retraction process of the inner support surface and the outer support surface, and the structure is simple and the design is ingenious.

[0042] The depth change rate refers to the speed at which the depth of the matching groove 101 changes along its own extending direction.

[0043] Specifically, Figure 5 As shown, due to the overlapping of two adjacent supporting surfaces, the two circumferentially adjacent matching grooves 101 are respectively an outer matching groove and an inner matching groove. In order to more intuitively display the depth change rate of the outer matching groove and the inner matching groove, the bottom surface of the matching groove 101 is now understood as a circular arc surface. At this time, the bottom surface of the inner matching groove is an arc with a radius of 10 mm, and the bottom surface of the outer matching groove is an arc with a radius of 15 mm. When the rod body 1 rotates a certain angle relative to the sleeve 2, the curvature of the arc with a radius of 10 mm changes faster, so the depth of the inner matching groove changes faster, and then when the support component 3 moves along the bottom surface in the inner matching groove, the retraction speed is also faster.

[0044] Furthermore, in order to simplify the structure of the support assembly 3, the mating end and the corresponding bottom surface 102 of the mating groove 101 are in sliding fit, and no additional mating parts are required. Since the sliding stroke of the mating end in the mating groove 101 is short, the relative friction between the mating end and the mating groove 101 does not have a significant impact on the movement process. It can be understood that as an alternative embodiment, the mating end can also be provided with a roller, and the mating end and the corresponding bottom surface 102 of the mating groove 101 are in rolling fit.

[0045] In this embodiment, each support component 3 includes a support rod 301 and a support blade 302. A through hole 201 is provided on the sleeve 2 for the support rod 301 to pass through. One end of the support rod 301 forms a mating end and the other end is fixedly connected to the support blade 302. The side of the support blade 302 away from the sleeve 2 forms a support surface. The through hole 201 can limit the movement of the support rod 301. When the support component 3 extends outward to reach the specified position, the position of the rod body 1 and the sleeve 2 is fixed. The through hole 201 prevents the support rod 301 from moving freely in the mating groove 101, thereby effectively fixing the position of the support component 3. The structure is simple and the operation is convenient.

[0046] Specifically, there is no limitation on the specific structure of the support rod 301 and the support blade 302. The length of the support rod 301 can be selected according to actual usage. The support rod 301 can be a cylindrical rod or a prismatic rod, which can be matched with the shape of the through hole 201. The support blade 302 can be a blade with a certain curvature, or a blade formed by connecting multiple flat plates at a certain angle. The support blade 302 can have a uniform thickness, or it can change along the extension direction, as long as they can cooperate with each other and reliably block the concrete.

[0047] Furthermore, the thickness of the supporting blade 302 is preferably 1 mm to 1.5 mm, and the material thereof can be steel or other materials with corresponding rigidity and stable chemical properties.

[0048] In this embodiment, the thickness of the support blades 302 gradually increases and then decreases along the circumferential direction. The end of each support blade 302 close to the adjacent support blade 302 is thinner to facilitate overlapping, and the middle part of the support blade 302 is thicker to improve the overall structural strength.

[0049] Specifically, the support rod 301 is fixedly connected to the middle part of the support blade 302. Since the middle part of the support blade 302 is thicker, the structural strength at the connection position between the support rod 301 and the support blade 302 is higher, which can effectively prevent it from breaking at the connection position when blocking concrete.

[0050] Preferably, in order to prevent the faster-moving support blade 302 from interfering with the slower-moving support blade 302 when the support blade 302 retracts, the support blade 302 has a certain curvature along the circumferential direction of the sleeve 2 .

[0051] In this embodiment, a limit block 303 is provided at the mating end of the support rod 301. The limit block 303 is slidably matched with the mating groove 101. The limit block 303 is suitable for limiting the support rod 301 from escaping from the through hole 201. The limit block 303 cannot pass through the through hole 201, thereby making it impossible for the mating end of the support rod 301 to escape from the through hole 201. The maximum extension length of the support rod 301 can be limited by the thickness of the limit block 303, and the structure is simple and reliable.

[0052] Specifically, there is no limitation on the structure of the limit block 303 , which may be a rectangular block, a sphere, etc. It needs to have a certain strength to prevent the limit block 303 from deforming, breaking, or other failure phenomena when the concrete squeezes the support rod 301 .

[0053] In this embodiment, an elastic member is further provided between the limit block 303 and the inner wall of the sleeve 2, and the elastic member is suitable for making the limit block 303 slide along the bottom surface 102 of the matching groove 101 toward the deeper side of the matching groove 101. When the support rod 301 is in an extended state, the elastic member is in a compressed state. Due to the presence of the elastic member, when the limit block 303 moves toward the deeper side of the matching groove 101, the elastic member can continuously apply a force toward the bottom of the matching groove 101 to the limit block 303, so that the limit block 303 fits as closely as possible to the bottom of the matching groove 101.

[0054] In this embodiment, there are multiple support rods 301 in each support assembly 3, and one support blade 302 is matched with the corresponding matching groove 101 through multiple support rods 301. Multiple support rods 301 are arranged at intervals along the axial direction of the sleeve 2. Multiple support rods 301 can improve the support strength and prevent the single support rod 301 from breaking when supporting. It can be understood that as an alternative embodiment, the number of support rods 301 can also be one. In order to ensure the support strength, the support rod 301 is in the shape of a long strip and extends along the axial direction of the sleeve 2.

[0055] Specifically, compared with a plate-shaped support rod with a larger contact area, a plurality of spaced support rods 301 can effectively reduce the contact area between the support rod 301 and the matching groove 101, reduce the friction generated between the two during movement, and enable the operator to more easily rotate the sleeve 2 and the rod body 1 relative to each other.

[0056] Preferably, four support assemblies 3 are arranged along the circumferential direction on the outer side of the sleeve 2, and each support assembly 3 includes a support blade 302, and one support blade 302 cooperates with the sleeve 2 and the rod body 1 through two support rods 301. It can be understood that the number of support assemblies 3 and the number of two support rods 301 in one support assembly 3 are not strictly limited, and the number of support assemblies 3 can be less than four or more than four, and the number of support rods 301 can also be one or more than two.

[0057] In this embodiment, the end of the rod body 1 is provided with a thread to facilitate cooperation with the fixing bolt. It can be understood that, as an alternative embodiment, the end of the rod body 1 can also be provided with a through hole extending in the radial direction, in which case, in cooperation with a positioning pin or a positioning block, the screw structure can also be fixedly connected to the template.

[0058] According to an embodiment of the present invention, on the other hand, a formwork system is provided, which includes: an inner formwork, an outer formwork, the above-mentioned screw structure and a plurality of locking members, the inner formwork and the outer formwork are arranged relative to each other; the screw structure is suitable for being passed through the inner formwork and the outer formwork; and a plurality of locking members cooperate with the corresponding screw structures to tie and fix the inner formwork and the outer formwork.

[0059] By using the above-mentioned screw structure in conjunction with multiple locking parts, the inner formwork and the outer formwork are tied and fixed, so that the components in the formwork system can be reused, which greatly reduces the loss of the formwork system during use and saves costs. At the same time, the screw structure is easy and quick to use and can also improve the pouring construction rhythm.

[0060] Preferably, the locking piece is a locking nut, and the inner formwork and the outer formwork can be formworks at joints or formworks used for cast-in-place structures. The formwork system of this embodiment can be applied to any construction process that requires the use of formworks.

[0061] In this embodiment, a sleeve 2 is sleeved on the rod body 1 and multiple support assemblies 3 are set. The support assemblies 3 cooperate with the matching grooves 101 on the rod body 1 to achieve extension and retraction. After the screw structure is placed at the specified position, the rod body 1 is rotated relative to the sleeve 2 in the positive direction, and the multiple support assemblies 3 extend outward and cooperate with each other to form a closed contact surface on the outside of the sleeve 2. At this time, the screw structure is fixed to the template and concrete can be poured. After the concrete is poured and hardened, the rod body 1 is rotated relative to the sleeve 2 in the opposite direction, and the multiple support assemblies 3 retract inward. At this time, a gap is generated between the support assemblies 3 and the concrete, and the screw structure can be completely pulled out of the concrete, eliminating the sleeve step. The whole process only requires two rotations, which effectively solves the problem that the existing tension screw structure has many working procedures and causes material waste.

[0062] In this embodiment, the depth change rate of the outer mating groove is smaller than the depth change rate of the inner mating groove. Since the two adjacent support surfaces are overlapped, this setting method can effectively avoid interference between the retraction process of the inner support surface and the outer support surface. The structure is simple and the design is ingenious.

[0063] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A screw structure, characterized in that: include: A rod body (1) has an outer wall on which a plurality of matching grooves (101) are arranged along the circumferential direction, and the depth of at least one section of the matching grooves (101) gradually decreases along the circumferential direction; A sleeve (2) is sleeved on the rod body (1), and the sleeve (2) and the rod body (1) are relatively rotatable; A plurality of support components (3) are arranged corresponding to the plurality of matching grooves (101), each of the support components (3) having a matching end and a supporting surface, the matching end passing through the sleeve (2) and matching with the corresponding matching groove (101), each of the support components (3) having an extended state extending outward and a retracted state retracting inward, and the plurality of support components (3) are suitable for extending outward so that the plurality of supporting surfaces are combined to form a contact surface in contact with concrete; When the rod body (1) rotates forwardly relative to the sleeve (2), the mating end moves toward the shallower side of the mating groove (101), and the supporting surface moves away from the sleeve (2), and the supporting assembly (3) is in an extended state; when the rod body (1) rotates backward relative to the sleeve (2), the mating end moves toward the deeper side of the mating groove (101), and the supporting surface moves closer to the sleeve (2), and the supporting assembly (3) is in a retracted state.

2. The screw structure according to claim 1, characterized in that: When a plurality of the support surfaces are combined to form the contact surface, two adjacent support surfaces are overlapped and matched.

3. The screw structure according to claim 2, characterized in that: In the two overlapping support surfaces, the matching groove (101) corresponding to the outer support surface forms an outer matching groove, and the matching groove (101) corresponding to the inner support surface forms an inner matching groove, and the depth change rate of the outer matching groove is smaller than the depth change rate of the inner matching groove, so that the retraction speed of the outer support surface is smaller than the retraction speed of the inner support surface.

4. The screw structure according to any one of claims 1 to 3, characterized in that: Each of the support assemblies (3) comprises a support rod (301) and a support blade (302); the sleeve (2) is provided with a through hole (201) for the support rod (301) to pass through; one end of the support rod (301) forms the mating end and the other end is fixedly connected to the support blade (302); a side of the support blade (302) away from the sleeve (2) forms a support surface.

5. The screw structure according to claim 4, characterized in that: The thickness of the supporting blade (302) gradually increases and then gradually decreases along the circumferential direction.

6. The screw structure according to claim 4, characterized in that: A limiting block (303) is provided at the mating end of the support rod (301), the limiting block (303) slidably engages with the mating groove (101), and the limiting block (303) is suitable for limiting the support rod (301) from falling out of the through hole (201).

7. The screw structure according to claim 6, characterized in that: An elastic member is also provided between the limit block (303) and the inner wall of the sleeve (2), and the elastic member is suitable for making the limit block (303) slide along the bottom surface (102) of the matching groove (101) toward the deeper side of the matching groove (101).

8. The screw structure according to claim 4, characterized in that: The number of the support rods (301) in each support assembly (3) is multiple, and one support blade (302) cooperates with the corresponding matching groove (101) through the multiple support rods (301), and the multiple support rods (301) are arranged at intervals along the axial direction of the sleeve (2).

9. The screw structure according to any one of claims 1 to 3, characterized in that: The end of the rod body (1) is provided with a thread.

10. A template system, characterized in that: include: Inner template and outer template are set relative to each other; The screw structure according to any one of claims 1 to 9, wherein the screw structure is suitable for being inserted into the inner mold plate and the outer mold plate; A plurality of locking members cooperate with the corresponding screw structures to tie and fix the inner template and the outer template.

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